From: Andre Noll <maan@systemlinux.org>
Date: Tue, 26 Jul 2011 20:47:20 +0000 (+0200)
Subject: alsa: Dump the configuration on startup.
X-Git-Tag: v0.4.9~11^2~2
X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=commitdiff_plain;h=43491f2e4c1a858ca439095b9f5d3215c7f42f03

alsa: Dump the configuration on startup.

Currently we log selected alsa parameters, but it is sometimes
useful to see the full configuration. This patch adds a call to
snd_pcm_dump() to alsa_init() which obtains the alsa hardware and
software configuration. It is printed for loglevels info and debug.
---

diff --git a/alsa_write.c b/alsa_write.c
index b89c8c31..a7539ba4 100644
--- a/alsa_write.c
+++ b/alsa_write.c
@@ -77,6 +77,7 @@ static int alsa_init(struct private_alsa_write_data *pad,
 	snd_pcm_sw_params_t *swparams;
 	snd_pcm_uframes_t start_threshold, stop_threshold;
 	snd_pcm_uframes_t period_size;
+	snd_output_t *log;
 	int err;
 
 	PARA_INFO_LOG("opening %s\n", conf->device_arg);
@@ -105,7 +106,6 @@ static int alsa_init(struct private_alsa_write_data *pad,
 		&pad->buffer_time, NULL);
 	if (err < 0 || !pad->buffer_time)
 		return -E_GET_BUFFER_TIME;
-	PARA_INFO_LOG("buffer time: %d\n", pad->buffer_time);
 	if (snd_pcm_hw_params_set_buffer_time_near(pad->handle, hwparams,
 			&pad->buffer_time, NULL) < 0)
 		return -E_SET_BUFFER_TIME;
@@ -113,8 +113,6 @@ static int alsa_init(struct private_alsa_write_data *pad,
 		return -E_HW_PARAMS;
 	snd_pcm_hw_params_get_period_size(hwparams, &period_size, NULL);
 	snd_pcm_hw_params_get_buffer_size(hwparams, &pad->buffer_frames);
-	PARA_INFO_LOG("buffer size: %lu, period_size: %lu\n", pad->buffer_frames,
-		period_size);
 	if (period_size == pad->buffer_frames)
 		return -E_BAD_PERIOD;
 	snd_pcm_sw_params_current(pad->handle, swparams);
@@ -137,9 +135,24 @@ static int alsa_init(struct private_alsa_write_data *pad,
 		* pad->channels / 8;
 	if (pad->bytes_per_frame <= 0)
 		return -E_PHYSICAL_WIDTH;
-	PARA_INFO_LOG("bytes per frame: %d\n", pad->bytes_per_frame);
 	if (snd_pcm_nonblock(pad->handle, 1))
 		PARA_ERROR_LOG("failed to set nonblock mode\n");
+	err = snd_output_buffer_open(&log);
+	if (err == 0) {
+		char *buf;
+		PARA_INFO_LOG("dumping alsa configuration\n");
+		snd_pcm_dump(pad->handle, log);
+		snd_output_buffer_string(log, &buf);
+		for (;;) {
+			char *p = strchr(buf, '\n');
+			if (!p) /* omit last output line, it's empty */
+				break;
+			*p = '\0';
+			PARA_INFO_LOG("%s\n", buf);
+			buf = p + 1;
+		}
+		snd_output_close(log);
+	}
 	return 1;
 }